Motion picture film propelling means



Oct. l, 1935. H. N EN5|GN Er AL 2,016,083

MOTION PICTURE FILM PROPELLING MEANS Filed July 17, 1932 2 Sheets-Sheet 1 Oct. l, 1935- H. N. ENslGN ET AL 2,016,083

MOTION PICTURE FILM PROPELLING MEANS Filed July 17, 19255 2 Sheets-Sheet 2 /Z Z7 l 30 122061220115' g jarrz's .E'nfzlgz, Harryjarztion.

Patented Oct. l, 1935 UNITED STATES MOTION PICTURE FILM PROPELLING MEANS Harris N. Ensign, Los Angeles, and Harry A. Hanson, West Los Angeles, Calif., assignors to Paramount Productions,

Inc., Los Angeles,

Calif., a corporation of Delaware Application July 17,1933, Serial No. 680,768

15 Claims.

ordinarily is continuously run in succession through the developing solution, the fixing bath, e

the water wash and nally the drier. The continuously moving film strip is thus in part undergoing wet treatment and in part being dried,

and since film expands when wet and contracts during drying, both elongation and shrinkage must be simultaneously Vcontended with in the same film strip. This condition gives rise to considerable difficulty in moving the lm strip through both the .wet and dry ends of the system, since the expanding wet film tends to become slack and slip on the drive rollers (which ordinarily are Without sprocket teeth), While the contracting film in the drier is simultaneously tending to become unduly tightened on the drive rollers.' These difliculties are so well appreciated in the art as to require no further elaboration here.

It is accordingly an object of the present invenv tion to provide an improved and simplified means for propelling film strips through liquid baths and driers, which will overcome the various diniculties referred to above.

In accordance with the present preferred form of our invention the film is wound over successive sets of smooth lm rollers, and each of such sets is provided with one driven film sprocket having nlm engaging teeth. Between successive sets of such rollers the film passes over elevators having yielding means placing the film under a certain tension. In one form or aspect of the invention this means is utilized to place only sufficient tension in the film to keep it properly taut, so as to remove slack that may come into the film, in the. case of a wet bath, or to yield with film shrinkage, in the case of a drier. In another form or aspect of the invention this means is designed to place sufficient tension in the film under all conditions of film elongation or film shrinkage, to give a frictional driving engagement between the smooth film rollers and the film strip. For instance, such tensioning means may comprise floating film rollers hangingv in loops formed in the film, and the amount of tension placed on the film may be controlled by weighting said rollers. In the case where this means is adjusted to tense the film sufliciently to give a driving engagement between the film and the smooth rollers of the successive roller sets mentioned above, said rollers are driven together with the toothed film sprocket to advance the film; but where it is not desired to drive the film by means of the smooth rollers the tension placed in the film need only be sufficient to take up any slack therein due to elongation, and it is not nec- 5 essary that the smooth rollers be d riven since in this case the toothed film sprockets are relied upon to advance the film. In either case the toothed film sprockets, in addition to their iilm driving function, serve to divide the system into 10 sections within each one of which the quantity of film, or number of sprocket holes, is maintained fixed. A progressive slippage of the film strip throughout the machine is thus positively prevented. 15

With this preliminary discussion in mind, the various features and aspects of the invention will be best understood by now referring to the following detailed description of a present preferred embodiment thereof, reference for this purpose 20 being had to the accompanying drawings, in which:

Fig. 1 is a vertical longitudinal section of the machine taken on line I--I of Fig. 2;

Fig. 2 is a plan view of the machine being taken 25 on line 2-2 of Fig. 1;

Fig. 3 is a vertical transverse section take on line 3 3 of Fig. 1;

Fig. 4 is a vertical detail section taken on line 4-4 of Fig. 1;

Fig. 5 is a detail section taken on line 5 -5 of Fig. 4;

Fig. 6 is a transverse section through a typical roller shaft showing the independent mounting of the film rollers thereon; and 35 Fig. 7 is an enlarged detail of a control device.

For the purpose of simplicity we show in the drawings merely the film rollers and supporting and driving means therefor, liquid tanks or drying chambers within which the aforementioned 4o may be used, in the case of wet or dry machines, respectively, being omitted since they may be of any usual or suitable construction. Moreover, it is to be understood that the specific embodiment herein described in detail is merely illus- 45 trative of one specific manner in which the broad invention may be carried intoA effect, from which description those skilled in the art will receive a broad understanding of our invention.

In the drawings numeral I0 designates gen- 50 erally a frame work upon which the rollers and driving devices may be mounted, the frame work here shown being made up of angle irons and comprising corner uprights I I, upper longitudinal members I2 and cross members I3, and lower 55 ofthe 'being 1I -ening longitudinal members I4 and cross members Il. Bpaeed longitudinally of frame III are pairs of vertical, film-roller shaftn supporting members 2li. here shown as of channel cross section (see Pig. and between each pair of which are mounted the upper and lower film roller shafts. In the present instance, alternate pairs of upper and lower roller shafts, here the first, third. fth, and so on. have no illm driving function andeomprisewhatareknowninthe artaselevators, while the remaining pairs, here the second, fourth, sixth and so on. have a nlm driving functlonandmaybereferredtoasdrivers.

The illm strip F, entering the machine from the left-hand end as viewed in Fig. l. passes first over an end upper roller Il, and is then wound spirally over the staggered upper and lower rollers on shafts Il and 2l to the other ends ofsaidshaftathenpassesforwardlytotheend roller of a series of rollers 21 on the upper shaft 3ll of the ilrst driver, and is spiralled around the staggered rollers 21 and 28 of the upper and lower shafts Il and Il. respectively, of the driver. From the last upper roller of the driver the film istaken forwardly to a second elevator, and from that elevator forwardly to a second driver,andsoontotheoutgoingendofthe machine Rollers Il on both shafts 2l and 28 preferably are mounted to rotate freely and individually on their shafts and are provided with roller bearingsasindicatedatflainliig. The upper roller shaft 2l of each elevator is suitably mounted at its two ends on channel members Il. The lower roller shaft 2l of each elevator is mounted at its two ends on a vertical movable carriage 31, said carriage Il having rollers 3l adapted to run on the vertical flanges of channel members 2li as tracks (see Fig. 5). For the purpose of adjusting the weight of the carriage, the carriage is provided with a horizontal cross bar Il adapted to carry a plurality of removable weights 4l, the proper weight of the carriage being adjusted by removing or adding said weights. 'Thus in the preferred form described the lower rollers of the elevators oat vertically and are supported by the film loops, the tension in the film strip depending upon the weight of the carriage as adjusted by means of weights 40.

Preferably. there is provided a yielding means for increasingly resisting elevation of the oatim roller carriage of the first elevator as said carriage is elevated. Although various expedients may be employed for this purpose, roller carriage Il of the rst elevator is shown in Figs. landlprovidedwithanarmcarryinga roller'll that supports an inclined weight arm 42 pivotally mounted at its upper end as at on channel member 2|. The lower end of arm l2 slidably carries a weight u having a set screw lla' for setting the weight at various positions on the arm., It will be obvious that weight arm Il exerts a downward force on arm lil and the film roller carriage Il, and that this downward vforceincreasesasthecarringerisesandswings theweight arm outwardly. A suitably calibrated scale ll is provided for reading the inclination ot arm I2, the scale reading being proportional to the downward force exerted by the weight arm on the carriage. By virtue of this provision the downward force on the film roller carriage increases as the film rollers rise with shortening film loops, the tendency of the device thus to yieldingly but increasingly resist shortof the film loops. The calibrated scale 4l aoiaoes indicates when the nlm loops are the proper length and the proper weight accordingly is on the nlm rollers, to give desired tension in the film `strip. This condition is obviously controllable either by adjusting the speed of the film drive s rollers to correspond with the speed at which the illm is supplied to the machine, or by ad- Justing the rate of film supply to the machine, and the reading of scale 45 therefore indicates the correct adiustment for proper illm tension. i0 The upper shaft 30 of each driver, in the villustrated embodiment, is mounted at one end in a bearing mounted on channel member 2l, and its other end extends outwardly through a bearing 41 on the opposite channel 2n and has l5 outside of said channel member a suitable drive means, as described more fully hereinafter. The illm rollers 21 on upper driver shafts Il) may be fast on their shafts, especially where it is desired that the smooth rollers on the driver shaft shall partake in the driving of the film; while in cases where dependence is placed entirely upon the sprockets for moving the hlm it is not necessary that the rollers be fast on the shaft. and if it is desired to avoid nlm drive by the 25 'smooth rollers the rollers mw of course be mounted rotatable on the shaft. In the form illustrated, however, the rollers are fast on the shaft, and are preferably, though not necessarily, formed integral with one another.

The lower shaft 3| of each driver is mounted at its two ends in supports 50 aiilxed to channel members `2li, and the film rollers 2t on lower shafts Il are relatively rotatable on the shafts and independent of one another, after the manner shown in Fig. 8.

While various drive means for the upper driver shaft may be employed to advantage, we prefer to employ air driven turbine wheels 80 mounted on the shaft ends just outside of bearings 41 (see 40 Fig. 3). Casings 6| are shown enclosing the wheels. Air under suitable pressure is supplied to the turbine wheels through feed pipes 62 extending within turbine casings BI, said feeders being supplied from a header 83 controlled by a 45 valve Il.

To insure equal drive speed throughout the inachine, upper driver shafts 30 are preferably drivingly interconnected. For instance, the extremities of the several shafts may have sprocket wheels 06 connected together by chains 6l.

From the last driver the illm strip is removed from the machine by means of a sprocket which is on the end of a shaft 10 also driven by a turbine wheel and also drlvingly intercom nected by sprocket and chain with the several driver shafts of the machine.

In the preferred embodiment described, the film rollers on the upper and lower shafts of the elevators and on the lower shafts of the drivers 50 are all independent and freely rotatable on their respective shafts, Vwhile the rollers on the upper or driven shafts of the drivers are fixed on their shafts, although in certain cases the latter rollers need not be fixed on their shafts, and the rollers as so far described are all smooth surface rollers without sprocket teeth. A toothed roller or sprocket l5 is then rigidly mounted on the driven shaft of each driver. This sprocket 15 preferably, though not necessarily, is located 70 substantially at the center of the upper driver shaft l0, as shown. As a result of the presence of these sprockets the quantity of film, or num- .ber of sprocket holes, between the sprockets 15 of successive drivers is maintained constant,the

sprockets positively precluding a general movement of slack in either direction through the machine.

The operation of the machine is then as follows: The film strip F will 'be understood to be continuously supplied from a feeding device which feeds it forwardly at substantially constant speed;

for instance, in case the instant machine is used smooth rollers.

as a drier, the film strip will be constantly fed into the machine from the usual take-out means at the outgoing end lof the wet machine.y 0r, if the present machine is embodied as a developer, the film strip may be supplied from any usual feeding device. In any case, the film strip may be considered as fed at substantially a constant rate to the ingoing end of the present machine. The incoming film strip islooped first over an elevator, then over a driver, then over a second elevator, and so on, to the final driver, and is finally taken out by the driven sprocket 69. The machine may be operated in either of two manners, or a combination of the two. depending upon kthe tension placed in the film strip by the weighting of the floating roller carriages of the elevators. Thus incase it is desired that only the toothed film sprockets` shall drive the film, the tension in the film `may be made only sufficient to take up the slack therein and not sufficient to give a frictional driving engagement with the surfaces of the smooth film rollers, and in this case it is of course largely immaterial whether or not the smooth rollers are loose or fixed on the driver shafts. But if it is desired that the smooth film sprockets shall partake in the drive of the film, or shall constitute' the main driving means, then the elevator carriages are weighted until the tension in the nlm strip is sufficient to give the necessary frictional driving engagement between the smooth rollers and the film. IIn the first case the film isA driven entirely by the sprockets, and in the last case either entirely or ,else partly by the The proper operative condition of the machine is not substantially altered by elongation of the film strip within the machine in the case of a wet machine', or with contraction, in the case of a drier, since these changes in length are taken up by vertical movement of the lower elevator rollers, without changing the tension on the film strip, and without the total-quantity of filmthe number of sprocket holeswithin the machine being affected.

The air lsupply to the drivingly inter-connected turbine wheels is preferably so regulated that the film drive rollers or sprockets are slightly overdriven, and are held back by the film strip. The position of the film tensionv controlled weight arm 42, as read by scale, indicates'when the machineiis'driven with proper power to take the film strip properly at just the speed at which it is supplied thereto. For instance, if the film is driven at too great a speed, the film loops in the first elevator will shorten, an arm 42 will rise accordingly, thereby indicating that the air supply to the turbines should be reduced. And if the arm lowers, indicating insufiicient drive power, the air supply should be increased. Arm I2 is thus an indicator of proper power on the drive turbines, and the arm position for proper operative conditions is marked on scale 45 whereat the film loops in the first elevator stabilize at constantl length with the drive rollers or sprockets slightly over-powered but held back by the film strip to the speed at which the nlm is fed to the machine. Y

It will be understood that the drawings and description are to be considered merely as illustrative of rather than restrictive on the broader s claims appended hereto, for various changes in design, structure and arrangement may be made without departing from the spirit and scope of said claims.

We claim: l0

1. In nlm propelling apparatus, the combination of two sets of smooth lm rollers over which a film strip may be successfully threaded, each such set comprising a drive shaft and a second shaft, a series of smooth' film rollers rigidly l5 mounted on said drive shaft and a series of smooth film rollers on said second shaft, a toothed film sprocket on each drive shaft, interconnected drive means for said drive shafts, and an elevator for the film strip between the outgoing and incoming 20 ends of said sets of film rollers, said elevator comprising an upper shaft and smooth film rollers independently rotatable thereon. and a lower vertically floating shaft and smooth film rollers independently rotatable thereon.

2.In film propelling apparatus, the combination of a plurality of successive sets of smooth film rollers over which a film strip may be successively threaded, each such set comprising a drive shaft and a' second shaft, a series of smooth 30 nlm rollers rigidly mounted on said drive shaft and a series of smooth rollers onAsaid second shaft, a toothed film roller on each drive shaft, interconnected drive means for the drive shafts, and elevators for the film strip between the out- 35 going and incoming ends of said 'successive sets of film rollers, each of said elevators comprislng an upper shaft and smooth film rollers independently rotatable thereon, and a lower vertically floating shaft and smooth nlm rollers in- 40 dependently rotatable thereon.

3. In film propelling apparatus, the combination of a plurality of successive sets of smooth film rollers over which a film strip may be successively threaded, each such set comprising a 45 drive shaft and a second shaft, a series of smooth film rollers mounted on said drive shaft and a series of smooth rollers on said second shaft, a toothed film roller rigidly mounted on each drive shaft, means for driving the drive shafts in unison, 50 and elevators for the film strip between the outgoing and incoming ends of said successive sets of film rollers, each of said elevators comprising an upper shaft and film rollers mounted thereon and a lower vertically floating shaft and film rollers independently rotatable thereon.

4. In film propelling apparatus, the combination of a plurality of successive sets of smooth film rollers over which a film strip may be successively threaded, each such set comprising `a drive shaft and a second shaft, a series of smooth film roller mounted on said drive shaft and a series of smooth rollers on each drive shaft, means for driving the drive shafts in unison, and elevators for the lm strip between the outgoing and incoming ends of said succsive sets of film rollers, each 'of said elevators comprising two shafts relatively movable one toward and from the other, film rollers mounted on said shafts over which the film strip may be passed, and means yieldingly acting to move said shafts apart to. take up slack in the film strip.

5. In film propelling apparatus, the combination of a film elevator comprising upper film rollers and vertically floating lower film rollers around 1I which a nlm strip may be convoluted, a plurality o! nlm drivers each comprising a set of nhn rollers, and said drivers arranged to take the nlm strip in succession, the first driver arranged to take the nlm strip from the outgoing end of said elevator, an elevator comprising upper nlm rollers and vertically floating lower nlm rollers between the outgoing and incoming ends of each pair of successive drivers, and means for driving certain rollers of the several drivers in unison.

6. In nlm propelling apparatus, the combination of a nlm elevator comprising upper nlm rollers and vertically noating lower nlm rollers around which a nlm strip may be convoluted, a plurality of nlm drivers each comprising a set of smooth nlm rollers and a toothed sprocket. and said drivers arranged to take the nlm strip in succession, the nrst driver arranged to take the nlm strip from the outgoing end of said elevator, an elevator comprising upper nlm rollers and vertically noating lower nlm rollers between the outgoing and incoming ends of each pair of successive drivers, and means for driving the toothed sprockets of said drivers in unison.

1. In nlm propelling apparatus, the combination of a nlm elevator comprising upper nlm rollor! and vertically noating lower nlm rollers around which a nlm strip may be convoluted, means placing an increasing downward force on said noating rollers as they are elevated by shortening of the nlm convolutions, a plurality of nlm drivers each comprising a set of nlm rollers, and said drivers arranged to take the nlm strip in succession, the nrst driver arranged to take the nlm strip from the outgoing end of said elevator, an elevator comprising upper nlm rollers and vertically noating lower nlm rollers between the outgoing and incomlng ends of each pair of successive drivers, and means for driving certain rollers of the several drivers in unison. Y

8. In nlm propelling apparatus, the combination of a nlm elevator comprising upper nlm rollers and vertically noating lower nlm rollers around which a nlm strip may be convoluted, means placing an increasing downward force on said noating rollers as they are elevated by shortening of the nlm convolutions, a plurality of nlm drivers each comprising a set of smooth nlm rollers and a toothed sprocket, and said drivers arranged to take the nlm strip in succession, the nrst driver arranged to take the nlm strip from the outgoing end of said elevator, an elevator comprising upper nlm rollers and vertically noating lower nlm rollers between the outgoing and incoming ends of each pair of successive drivers, and means for driving the toothed sprockets oi' said drivers in unison.

9. In nlm propelling apparatus, the combination of two sets of smooth nlm rollers over which a nlm strip may be successfully threaded, each auch set comprising a drive shaft and a second shaft, a series of smooth nlm rollers mounted on said drive shaft anda series of smooth nlm rollers onsaid second shaft, a toothed nlm sprocket on each drive shaft, interconnected drive means for said drive shafts, and an elevator for the nlm strip between the outgoing and incoming ends of said sets of nlm rollers, said elevator comprising an upper shaft and smooth nlm rollers independently rotatable thereon, and a lower vertically noating shaft and smooth nlm rollers independently rotatable thereon.

10. In nlm propelling apparatus, the combina tion of a plurality of sets of nlm rollers, each such set comprising a series of smooth rollers over which a nlm strip may be passed in succession and including a driven toothed sprocket over which the nlm also passes, and nlm tensing means acting on the nlm at a point between the last roller of one such set and the nrst roller of the next such set.

l1. In nlm propelling apparatus, the combination of a plurality of sets oi nlm rollers, each such set comprising a series of smooth rollers over which a nlm strip may be passed in succession and including a toothed nlm sprocket, means for driv ing certain of the smooth rollers and said toothed sprocket, and nlm tensing means acting on the nlm at a point between the last roller of one such set and the nrst roller of the next such set.

l2. In nlm propelling apparatus, the combination of a plurality of sets of nlm rollers, each such set comprising a series of smooth rollers over which a nlm strip may be passed in succession and including a driven toothed sprocket over which the nlm also passes, and nlm tensing means acting on the nlm at a point between the last roller of one such set and the nrst roller of the next such set, said means comprising an elevator consisting of upper nlm rollers and vertically noating lower nlm rollers.

13. In nlm propelling apparatus, the combination of a plurality of sets of nlm rollers, each such set comprising a series of smooth rollers over which a nlm strip may be passed in succession and including a driven toothed sprocket over which the nlm also passes, an elevator for the nlm strip between the last roller of one such set and the nrst roller of the next such set, each such elevator comprising a set of nlm rollers over which the nlm strip is threaded, and means for taking up slack in the nlm strip on said elevator.

14. In nlm developing apparatus, the combination oi a plurality of nlm drivers each comprising a set of nlm rollers, and said drivers arranged to take the nlm strip in succession, an elevator comprising upper nlm rollers and vertically noating lower nlm rollers between the outgoing and incoming ends of each pair of successive drivers, and means for driving certain rollers of the several drivers in unison.

l5. In nlm developing apparatus, the combination of a plurality of nlm drivers each comprising a set of smooth nlm rollers and a toothed nlm sprocket, and said drivers arranged to take the nlm strip in succession, an elevator comprising upper nlm rollers and vertically noating lower nlm rollers between the outgoing and incoming ends of each pair of successive drivers, and means for driving the toothed sprockets of said drivers in unison.

HARRIS N. ENSIGN. HARRY A. HANSON. 

